Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

S,S' in the Lorentz transform.

  1. Nov 22, 2009 #1
    When we use the Lorentz transform. We must have S,S' frame.
    How can we choose S,S' frame?
  2. jcsd
  3. Nov 23, 2009 #2


    User Avatar
    Science Advisor
    Homework Helper

    The S frame is the frame "at rest". Usually, you are in the S frame yourself. But if you are in a moving spaceship, for example, and you are asked what people on a planet read on your clock as you whizz by, they are in the "rest frame" S and you are in the moving frame S'.
  4. Nov 23, 2009 #3
    Thank you so much.
  5. Nov 23, 2009 #4


    User Avatar
    Science Advisor

    S and S' can be any two frames moving with a constant relative velocity between them.
    It is not necessary that one of them be "at rest".
  6. Nov 23, 2009 #5


    User Avatar
    Science Advisor

    In usual usage, S must be an inertial frame, which is defined to be one in which Maxwell's equations or your favourite laws of physics in their *standard form* are true.

    If you use any particular Lorentz transformation on S, you will obtain S', and S' will also be an inertial frame.

    Basically, it tells you how to find all other inertial frames given a particular inertial frame.
  7. Nov 23, 2009 #6
    So the rest of the laws of physics that aren't my "favourites" don't have to be true to call a frame inertial?
  8. Nov 23, 2009 #7


    User Avatar
    Science Advisor

    Yeah! Which ones don't you like? :smile:
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook